Integrated circuit (IC) devices are widely used in electronic products. An IC device usually includes many different components enclosed in an IC package (or IC chip). Different components of an IC may perform different activities. Some IC devices may operate at a lower power mode for some activities and operate at a higher power mode for other activities. Some of these IC devices may use a crystal oscillator as a timer to switch between different power modes. In some cases, a crystal oscillator may be unsuitable for switching function in some IC devices.